U.S. patent number 10,854,687 [Application Number 15/898,346] was granted by the patent office on 2020-12-01 for organic light emitting display device.
This patent grant is currently assigned to SAMSUNG DISPLAY CO., LTD.. The grantee listed for this patent is Samsung Display Co. Ltd.. Invention is credited to Sun Kyu Joo, Byung Chul Kim, In Ok Kim, Su Jeong Kim, Sung Chul Kim, Yui Ku Lee, Jae Jin Lyu, Hye Ran Mun, Keun Chan Oh, In Seok Song.
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United States Patent |
10,854,687 |
Joo , et al. |
December 1, 2020 |
Organic light emitting display device
Abstract
An organic light emitting display device comprising: a
substrate; a first pixel electrode disposed on the substrate; a
pixel defining film disposed on the first pixel electrode and
having a first opening at least partially exposing the first pixel
electrode; a first organic light emitting layer disposed on the
pixel defining film and overlapping with the first opening of the
pixel defining film; and a black matrix disposed on the first
organic light emitting layer and having a first opening overlapping
with the first organic light emitting layer. Light having passed
through the first opening of the black matrix is one of red light,
green light, and blue light. The first opening of the black matrix
may have a shape with a curved portion.
Inventors: |
Joo; Sun Kyu (Suwon-si,
KR), Kim; Byung Chul (Suwon-si, KR), Kim;
Sung Chul (Seongnam-si, KR), Kim; Su Jeong
(Yongin-si, KR), Kim; In Ok (Osan-si, KR),
Mun; Hye Ran (Yangju-si, KR), Song; In Seok
(Pocheon-si, KR), Oh; Keun Chan (Hwaseong-si,
KR), Lyu; Jae Jin (Yongin-si, KR), Lee; Yui
Ku (Asan-si, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Display Co. Ltd. |
Yongin-si |
N/A |
KR |
|
|
Assignee: |
SAMSUNG DISPLAY CO., LTD.
(Yongin-si, KR)
|
Family
ID: |
1000005216985 |
Appl.
No.: |
15/898,346 |
Filed: |
February 16, 2018 |
Prior Publication Data
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|
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Document
Identifier |
Publication Date |
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US 20190013363 A1 |
Jan 10, 2019 |
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Foreign Application Priority Data
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|
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Jul 4, 2017 [KR] |
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10-2017-0085074 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L
27/322 (20130101); H01L 51/56 (20130101); H01L
51/5072 (20130101); H01L 51/5056 (20130101); H01L
51/5092 (20130101); H01L 27/3211 (20130101); H01L
51/5203 (20130101); H01L 51/5284 (20130101); H01L
27/326 (20130101); H01L 27/3246 (20130101); H01L
27/3283 (20130101) |
Current International
Class: |
H01L
27/32 (20060101); H01L 51/56 (20060101); H01L
51/52 (20060101); H01L 51/50 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2015-144087 |
|
Jan 2014 |
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JP |
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2016-173460 |
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Mar 2015 |
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JP |
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10-2014-0083988 |
|
Jul 2014 |
|
KR |
|
10-2016-0030444 |
|
Mar 2016 |
|
KR |
|
10-2017-0015601 |
|
Feb 2017 |
|
KR |
|
Other References
Extended European Search Report dated Nov. 7, 2018 of the
corresponding European application No. 18164634.0. cited by
applicant.
|
Primary Examiner: Tobergte; Nicholas J
Assistant Examiner: Ly; Kien C
Attorney, Agent or Firm: Kyle Park Reed & Houtteman
PLLC
Claims
What is claimed is:
1. An organic light emitting display device comprising: a
substrate; a first pixel electrode disposed on the substrate; a
pixel defining film disposed on the first pixel electrode and
having a first opening at least partially exposing the first pixel
electrode; a first organic light emitting layer disposed on the
pixel defining film and overlapping with the first opening of the
pixel defining film; and a black matrix disposed on the first
organic light emitting layer and having a first opening overlapping
with the first organic light emitting layer, wherein light having
passed through the first opening of the black matrix is one of red
light, green light, and blue light, and the first opening of the
black matrix has a circular shape which is composed of assemblies
of dots that are spaced a same distance apart from a virtual center
point of the first opening of the black matrix.
2. The organic light emitting display device of claim 1, wherein
the first opening of the black matrix has a smaller area than the
first opening of the pixel defining film.
3. The organic light emitting display device of claim 1, further
comprising a color filter disposed to cover the first opening of
the black matrix.
4. The organic light emitting display device of claim 3, further
comprising an encapsulation layer disposed on the pixel defining
film, wherein the black matrix and the color filter are disposed on
the encapsulation layer.
5. The organic light emitting display device of claim 3, wherein a
width of a region in which the black matrix overlaps with one side
of the color filter ranges from 6 .mu.m to 12 .mu.m.
6. The organic light emitting display device of claim 1, wherein
the first opening of the pixel defining film is substantially
circular.
7. The organic light emitting display device of claim 1, further
comprising: a second pixel electrode disposed on the same layer as
the first pixel electrode; and a second organic light emitting
layer disposed on the pixel defining film and overlapping with the
second pixel electrode, wherein the pixel defining film further
comprises a second opening at least partially exposing the second
pixel electrode, the black matrix further comprises a second
opening overlapping with the second organic light emitting layer,
and light having passed through the second opening of the black
matrix has a different display color from the light having passed
through the first opening of the black matrix.
8. The organic light emitting display device of claim 7, wherein
the second opening of the black matrix has a shape with a curved
portion.
9. The organic light emitting display device of claim 7, further
comprising: a third pixel electrode disposed on the same layer as
the first pixel electrode; and a third organic light emitting layer
disposed on the pixel defining film and overlapping with the third
pixel electrode, wherein the pixel defining film further comprises
a third opening at least partially exposing the third pixel
electrode, the black matrix further comprises a third opening
overlapping with the third organic light emitting layer, and light
having passed through the third opening of the black matrix, the
light having passed through the first opening of the black matrix,
and the light having passed through the second opening of the black
matrix have different display colors.
10. The organic light emitting display device of claim 9, wherein a
shortest distance from the second opening of the pixel defining
film to the first opening of the pixel defining film is the same as
a shortest distance from the second opening of the pixel defining
film to the third opening of the pixel defining film.
11. The organic light emitting display device of claim 9, further
comprising a first color filter layer disposed on the black matrix
and including a first opening overlapping with the first opening of
the black matrix and a second opening overlapping with the second
opening of the black matrix, wherein the first color filter layer
overlaps with the third opening of the black matrix and surrounds
the first opening of the black matrix and the second opening of the
black matrix.
12. The organic light emitting display device of claim 11, wherein
the first color filter layer is a blue color filter layer for
transmitting blue light.
13. The organic light emitting display device of claim 11, further
comprising: a first color filter overlapping with the first opening
of the first color filter layer; and a second color filter
overlapping with the second opening of the first color filter
layer.
14. The organic light emitting display device of claim 11, further
comprising a second color filter layer disposed on the first color
filter layer and overlapping with the first opening of the black
matrix, wherein the second color filter layer surrounds the second
opening of the first color filter layer.
15. The organic light emitting display device of claim 9, further
comprising: a first color filter overlapping with the first opening
of the black matrix; a second color filter overlapping with the
second opening of the black matrix; and a first color filter layer
disposed on the first color filter and the second color filter,
wherein the first color filter layer overlaps with the third
opening of the black matrix and surrounds the first opening of the
black matrix and the second opening of the black matrix.
16. An organic light emitting display device comprising: a
substrate; a first pixel electrode disposed on the substrate; a
pixel defining film disposed on the first pixel electrode and
having a first opening at least partially exposing the first pixel
electrode; a first organic light emitting layer disposed on the
pixel defining film and overlapping with the first opening of the
pixel defining film; and a black matrix disposed on the first
organic light emitting layer and having a first opening overlapping
with the first organic light emitting layer, wherein the first
opening of the black matrix has a smaller area than the first
opening of the pixel defining film, and the first opening of the
black matrix has a circular shape which is composed of assemblies
of dots that are spaced a same distance apart from a virtual center
point of the first opening of the black matrix.
17. The organic light emitting display device of claim 16, wherein
the first opening of the pixel defining film is substantially
circular.
18. The organic light emitting display device of claim 16, wherein
light having passed through the first opening of the black matrix
is one of red light, green light, and blue light.
19. The organic light emitting display device of claim 16, further
comprising a first color filter disposed to cover the first opening
of the black matrix, wherein a width of a region in which the black
matrix overlaps with one side of the color filter ranges from 6
.mu.m to 12 .mu.m.
20. The organic light emitting display device of claim 16, further
comprising a second pixel electrode and a third pixel electrode
disposed on the same layer as the first pixel electrode, wherein
the pixel defining film further comprises a second opening at least
partially exposing the second pixel electrode and a third opening
at least partially exposing the third pixel electrode, the black
matrix further comprises a second opening overlapping with the
second pixel electrode and a third opening overlapping with the
third pixel electrode, and light having passed through the first
opening of the black matrix, light having passed through the second
opening of the black matrix, and light having passed through the
third opening of the black matrix have different display colors
from one another.
21. The organic light emitting display device of claim 20, further
comprising a first color filter layer disposed on the black matrix
and including a first opening overlapping with the first opening of
the black matrix and a second opening overlapping with the second
opening of the black matrix, wherein the first color filter layer
overlaps with the third opening of the black matrix and surrounds
the first opening of the black matrix and the second opening of the
black matrix.
22. The organic light emitting display device of claim 21, wherein
the first color filter layer is a blue color filter layer for
transmitting blue light.
23. The organic light emitting display device of claim 21, further
comprising a yellow color filter overlapping with the first opening
and the second opening of the first color filter layer.
24. The organic light emitting display device of claim 21, further
comprising a second color filter layer disposed on the first color
filter layer and overlapping with the first opening of the black
matrix.
25. An organic light emitting display device comprising: a
substrate; a first pixel electrode disposed on the substrate; a
pixel defining film disposed on the first pixel electrode and
having a first opening at least partially exposing the first pixel
electrode; a first organic light emitting layer disposed on the
pixel defining film and overlapping with the first opening of the
pixel defining film; and a black matrix disposed on the first
organic light emitting layer and having a first opening overlapping
with the first organic light emitting layer, wherein light having
passed through the first opening of the black matrix is one of red
light, green light, and blue light, and the first opening of the
black matrix has a circular shape or a non-elliptical polygonal
shape similar to a circle which is composed of assemblies of dots
that are each spaced apart from a center point of the opening at a
distance defined by the center point of the first opening and a
circular or polygonal shaped perimeter of the first opening.
Description
This application claims priority to Korean Patent Application No.
10-2017-0085074 filed on Jul. 4, 2017 in the Korean Intellectual
Property Office, and all the benefits accruing therefrom under 35
U.S.C. 119, the contents of which in its entirety are herein
incorporated by reference.
BACKGROUND
1. Field of the Disclosure
The present disclosure relates to an organic light emitting display
device.
2. Description of the Related Art
Along with the development of multimedia, display devices are
becoming increasingly important. In response to this, several kinds
of display devices such as a liquid crystal display (LCD) and an
organic light emitting display (OLED) have been used.
Among the display devices, OLEDs display images by using organic
light emitting devices that generate light through recombination of
electrons and holes. OLEDs have benefits such as a fast response
time, high brightness, a large viewing angle, and low power
consumption.
SUMMARY
Aspects of the present disclosure provide an organic light emitting
display device capable of alleviating reflected color separation
due to external light.
Aspects of the present disclosure also provide an organic light
emitting display device capable of managing uniform dispersion and
reducing reflectivity.
Aspects of the present disclosure also provide an organic light
emitting display device capable of reducing costs because no
polarizing plate is used.
It should be noted that objects of the present inventive concept
are not limited to the above-described objects, and other objects
of the present inventive concept will be apparent to those skilled
in the art from the following descriptions.
An exemplary embodiment of the present inventive concept discloses
a display device comprising: An organic light emitting display
device comprising: a substrate; a first pixel electrode disposed on
the substrate; a pixel defining film disposed on the first pixel
electrode and having a first opening at least partially exposing
the first pixel electrode; a first organic light emitting layer
disposed on the pixel defining film and overlapping with the first
opening of the pixel defining film; and a black matrix disposed on
the first organic light emitting layer and having a first opening
overlapping with the first organic light emitting layer. Light
having passed through the first opening of the black matrix is one
of red light, green light, and blue light. The first opening of the
black matrix may have a shape with a curved portion.
An exemplary embodiment of the present inventive concept also
discloses a display device comprising: an organic light emitting
display device comprising: a substrate; a first pixel electrode
disposed on the substrate; a pixel defining film disposed on the
first pixel electrode and having a first opening at least partially
exposing the first pixel electrode; a first organic light emitting
layer disposed on the pixel defining film and overlapping with the
first opening of the pixel defining film; and a black matrix
disposed on the first organic light emitting layer and having a
first opening overlapping with the first organic light emitting
layer. The first opening of the back matrix may have a smaller area
than the first opening of the pixel defining film.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects and features of the present disclosure
will become more apparent by describing in detail exemplary
embodiments thereof with reference to the attached drawings, in
which:
FIG. 1 is a plan view showing a pixel layout of an organic light
emitting display device according to an embodiment of the present
inventive concept;
FIG. 2 is a sectional view taken along line I-I' shown in FIG.
1;
FIG. 3 is a view for comparison between FIG. 1, which is a plan
view of a first pixel, and FIG. 2, which is a sectional view taken
along line I-I';
FIG. 4 is a plan view showing a color filter and an opening of a
black matrix of an organic light emitting display device according
to a comparative example;
FIG. 5 is a view showing that color separation is alleviated in an
organic light emitting display device according to an embodiment of
the present inventive concept;
FIG. 6 is a view showing color separation in the organic light
emitting display device according to the comparative example shown
in FIG. 4;
FIG. 7 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept;
FIG. 8 is a sectional view taken along line II-II' shown in FIG.
7;
FIGS. 9A and 9B is a view showing examples of the shape of an
opening of a black matrix shown in FIG. 7;
FIG. 10 is a view showing an interval between openings of a pixel
defining film adjacent to an organic light emitting display device
according to another embodiment of the present inventive
concept;
FIG. 11 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept;
FIG. 12 is a sectional view taken along line III-III' shown in FIG.
11;
FIG. 13 is a plan view showing an opening of a black matrix and a
color filter of an organic light emitting display device according
to another embodiment of the present inventive concept;
FIG. 14 is a plan view showing an opening of a black matrix and a
color filter of an organic light emitting display device according
to still another embodiment of the present inventive concept;
FIG. 15 is a plan view showing a color filter and an opening of a
black matrix of an organic light emitting display device according
to a comparative example;
FIG. 16 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept;
FIG. 17 is a sectional view taken along line IV1-IV1', line
IV2-IV2', and line IV3-IV3' shown in FIG. 16;
FIG. 18 is a diagram illustrating an improvement of reflective
dispersion of the organic light emitting display device shown in
FIG. 16;
FIGS. 19, 20, 21, 22, 23, 24, 25 and 26 are diagrams illustrating a
process of manufacturing the organic light emitting display device
shown in FIG. 16;
FIG. 27 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept;
FIG. 28 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept;
FIG. 29 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept;
FIG. 30 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept;
FIG. 31 is a plan view showing a pixel layout of an organic light
emitting display device according to still another embodiment of
the present inventive concept; and
FIG. 32 is a sectional view taken along line V1-V1', line V2-V2',
and line V3-V3' shown in FIG. 31.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In the following description, for the purposes of explanation,
numerous specific details are set forth in order to provide a
thorough understanding of various exemplary embodiments. It is
apparent, however, that various exemplary embodiments may be
practiced without these specific details or with one or more
equivalent arrangements. In other instances, well-known structures
and devices are shown in block diagram form in order to avoid
unnecessarily obscuring various exemplary embodiments.
In the accompanying figures, the size and relative sizes of layers,
films, panels, regions, etc., may be exaggerated for clarity and
descriptive purposes. Also, like reference numerals denote like
elements.
When an element or layer is referred to as being "on," "connected
to," or "coupled to" another element or layer, it may be directly
on, connected to, or coupled to the other element or layer or
intervening elements or layers may be present. When, however, an
element or layer is referred to as being "directly on," "directly
connected to," or "directly coupled to" another element or layer,
there are no intervening elements or layers present. For the
purposes of this disclosure, "at least one of X, Y, and Z" and "at
least one selected from the group consisting of X, Y, and Z" may be
construed as X only, Y only, Z only, or any combination of two or
more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ.
Like numbers refer to like elements throughout. As used herein, the
term "and/or" includes any and all combinations of one or more of
the associated listed items.
Although the terms first, second, etc. may be used herein to
describe various elements, components, regions, layers, and/or
sections, these elements, components, regions, layers, and/or
sections should not be limited by these terms. These terms are used
to distinguish one element, component, region, layer, and/or
section from another element, component, region, layer, and/or
section. Thus, a first element, component, region, layer, and/or
section discussed below could be termed a second element,
component, region, layer, and/or section without departing from the
teachings of the present disclosure.
Spatially relative terms, such as "beneath," "below," "lower,"
"above," "upper," and the like, may be used herein for descriptive
purposes, and, thereby, to describe one element or feature's
relationship to another element(s) or feature(s) as illustrated in
the drawings. Spatially relative terms are intended to encompass
different orientations of an apparatus in use, operation, and/or
manufacture in addition to the orientation depicted in the
drawings. For example, if the apparatus in the drawings is turned
over, elements described as "below" or "beneath" other elements or
features would then be oriented "above" the other elements or
features. Thus, the exemplary term "below" can encompass both an
orientation of above and below. Furthermore, the apparatus may be
otherwise oriented (e.g., rotated 90 degrees or at other
orientations), and, as such, the spatially relative descriptors
used herein interpreted accordingly.
The terminology used herein is for the purpose of describing
particular embodiments and is not intended to be limiting. As used
herein, the singular forms, and "the" are intended to include the
plural forms as well, unless the context clearly indicates
otherwise. Moreover, the terms "comprises," "comprising,"
"includes," and/or "including," when used in this specification,
specify the presence of stated features, integers, steps,
operations, elements, components, and/or groups thereof, but do not
preclude the presence or addition of one or more other features,
integers, steps, operations, elements, components, and/or groups
thereof.
Various exemplary embodiments are described herein with reference
to sectional illustrations that are schematic illustrations of
idealized exemplary embodiments and/or intermediate structures. As
such, variations from the shapes of the illustrations as a result,
for example, of manufacturing techniques and/or tolerances, are to
be expected. Thus, exemplary embodiments disclosed herein should
not be construed as limited to the particular illustrated shapes of
regions, but are to include deviations in shapes that result from,
for instance, manufacturing. For example, an implanted region
illustrated as a rectangle will, typically, have rounded or curved
features and/or a gradient of implant concentration at its edges
rather than a binary change from implanted to non-implanted region.
Likewise, a buried region formed by implantation may result in some
implantation in the region between the buried region and the
surface through which the implantation takes place. Thus, the
regions illustrated in the drawings are schematic in nature and
their shapes are not intended to illustrate the actual shape of a
region of a device and are not intended to be limiting.
Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
disclosure is a part. Terms, such as those defined in commonly used
dictionaries, should be interpreted as having a meaning that is
consistent with their meaning in the context of the relevant art
and will not be interpreted in an idealized or overly formal sense,
unless expressly so defined herein.
Hereinafter, exemplary embodiments will be described with reference
to the accompanying drawings.
FIG. 1 is a plan view showing a pixel layout of an organic light
emitting display device according to an embodiment of the present
inventive concept.
Referring to FIG. 1, a plurality of pixel units including first to
fourth pixels PX1 to PX4 may be disposed in a pixel area DA.
An arrangement of the first to fourth pixels PX1 to PX4 will be
described with reference to FIG. 1. The first pixel PX1 and the
third pixel PX3 may be disposed adjacent to each other in a first
direction d1. The second pixel PX2 and the fourth pixel PX4 may be
disposed adjacent to each other in the first direction d1. The
first pixel PX1 and the second pixel PX2 may be disposed adjacent
to each other in a second direction d2, which is a diagonal
direction with respect to the first direction d1 and a third
direction d3 which is perpendicular to the first direction d1. The
third pixel PX3 and the fourth pixel PX4 may be disposed adjacent
to each other in the second direction d2.
A plurality of color filters may include first, second, and third
color filters CF1, CF2, and CF3. In this disclosure, the first
color filter CF1 may be a red color filter, the second color filter
CF2 may be a green color filter, and the third color filter CF3 may
be a blue color filter. However, the first color filter CF1, the
second color filter CF2, and the third color filter CF3 are not
limited to red, green, and blue color filters, respectively. For
example, each of the first color filter CF1, the second color
filter CF2, and the third color filter CF3 may be any one of a cyan
color filter, a magenta color filter, and a yellow color filter.
Here, as an example, it will be described that the first color
filter CF1 is a red color filter, the second color filter CF2 is a
green color filter, and the third color filter CF3 is a blue color
filter. In this disclosure, the same reference numeral will be used
to describe color filters which transmit light in the same
wavelength region.
The first pixel PX1 may overlap with the first color filter CF1.
The second pixel PX2 and the fourth pixel PX4 may overlap with the
second color filter CF2. Also, the third pixel PX3 may overlap with
the third color filter CF3. Thus, the first pixel PX1 may display a
red color, and the second pixel PX2 and the fourth pixel PX4 may
display a green color. Also, the third pixel PX3 may display a blue
color.
Here, the first to fourth pixels PX1 to PX4, which display red,
green, blue, and green colors, may constitute a single pixel unit.
That is, as a red-green-blue-green (RGBG) pentile, the first to
fourth pixels PX1 to PX4 may be disposed in the pixel area DA.
However, the arrangement of the plurality of pixels disposed in the
pixel area DA is not limited to that shown in FIG. 1. For example,
the arrangement of the plurality of pixels may vary depending on
the display colors of the pixels, the resolution and the aperture
ratio of an applied organic light emitting display device, and so
on.
In this disclosure, the expression "a first element and a second
element overlap with each other" indicates that the first element
overlaps with the second element when projected onto a first
substrate 110.
Here, relations between a first pixel electrode 121, an opening
OP1a of a pixel defining film 130 (see FIG. 2), and an opening OP2a
of a black matrix BM will be described on the basis of the first
pixel PX1.
The first pixel PX1 may include the first pixel electrode 121. The
first pixel electrode 121 may be partially exposed by the opening
OP1a of the pixel defining film 130 (see FIG. 2). The first pixel
electrode 121 may overlap with the opening OP1a of the pixel
defining film 130 (see FIG. 2) and the opening OP2a of the black
matrix BM.
The first pixel electrode 121 may overlap with the first color
filter CF1. More specifically, the first color filter CF1 may
overlap with the first pixel electrode 121 by covering the opening
OP2a of the black matrix BM. Thus, the first pixel PX1 may display
a red color because light emitted from a first organic light
emitting layer 141 (see FIG. 2) becomes red after passing through
the first color filter CF1.
As an example, the first pixel electrode 121 may have a rhombus
shape. Also, as an example, the opening OP1a of the pixel defining
film 130 (see FIG. 2) may have a rhombus shape. Here, the rhombus
shape may include the shape of a figure that is substantially the
same as a rhombus (e.g., a quadrangle) in consideration of a
manufacturing process or the like, as well as the shape of a
rhombus. The shape of the first pixel electrode 121 and the shape
of the opening OP1a of the pixel defining film 130 (see FIG. 2) are
not limited to those shown in FIG. 1. That is, the shape of the
first pixel electrode 121 and the shape of the opening OP1a of the
pixel defining film 130 (see FIG. 2) may vary depending on the
arrangement of the plurality of pixels.
The shape of the opening OP2a of the black matrix BM may have a
curved portion. In this disclosure, the term "curved portion" is
defined as a region having a predetermined curvature. Thus, the
shape of the opening OP2a of the black matrix BM may include a
region having a predetermined curvature, i.e., a curved
portion.
More specifically, the opening OP2a of the black matrix BM may have
a substantially circular shape. That is, the planar shape of the
opening OP2a of the black matrix BM may be a curved line which is
composed of assemblies of dots that are spaced a certain distance
apart from a virtual center point cp. The opening OP2a of the black
matrix BM may omnidirectionally and uniformly induce diffraction of
light on the basis of the virtual center point cp. This will be
described in detail below with reference to FIGS. 3 to 6. In this
disclosure, the circular shape may include the shape of a polygon
substantially close to a circle, an ellipse, or a figure having at
least one curved portion in consideration of a manufacturing
process or the like, as well as the shape of a circle. Here, in
this disclosure, a polygon close to a circle, an ellipse, or a
figure with at least one curved portion is described as a "circular
shape."
FIG. 2. is a sectional view taken along line I-I' shown in FIG. 1.
The following description will be provided with reference to the
first pixel PX1, as described above.
Referring to FIGS. 1 and 2, the organic light emitting display
device according to an embodiment of the present inventive concept
may include the first substrate 110, the first pixel electrode 121,
the pixel defining film 130, the first organic light emitting layer
141, a common electrode 150, an encapsulation layer 160, the black
matrix BM, the first color filter CF1, the second color filter CF2,
and the third color filter CF3.
The first substrate 110 may be an insulating substrate. As an
example, the first substrate 110 may include materials such as
glass, quartz, and polymer resins. Here, the polymer materials may
include polyethersulphone (PES), polyacrylate (PA), polyarylate
(PAR), polyetherimide (PEI), polyethylenenaphthalate (PEN),
polyethyleneterephthalate (PET), polyphenylenesulfide (PPS),
polyallylate, polyimide (PI), polycarbonate (PC),
cellulosetriacetate (CAT), cellulose acetate propionate (CAP), or a
combination thereof. As another example, the first substrate 110
may be a flexible substrate including polyimide (PI).
The first pixel electrode 121 may be disposed on the first
substrate 110. Although not shown, other elements may be
additionally disposed between the first substrate 110 and the first
pixel electrode 121. As an example, the other elements may include
a buffer layer, a conductive wire, an insulation layer, and a
plurality of thin-film transistors. Here, the plurality of
thin-film transistors may use amorphous silicon, polysilicon, low
temperature polysilicon (LTPS), an oxide semiconductor, an organic
semiconductor, or the like as a channel layer. The plurality of
thin-film transistors may have different types of channel layers.
As an example, both of a thin-film transistor including an oxide
semiconductor and a thin-film transistor including LTPS may be
included in one pixel, in consideration of roles or manufacturing
processes of the thin-film transistors.
As an example, the first pixel electrode 121 may be an anode
electrode. When the first pixel electrode 121 is an anode
electrode, the first pixel electrode 121 may include a high work
function material to facilitate hole injection. Also, the first
pixel electrode 121 may be a reflective electrode, a
semitransparent electrode, or a transparent electrode. As an
example, the first pixel electrode 121 may include a reflective
material. The reflective material may include, as an example, one
or more selected from the group consisting of silver (Ag),
magnesium (Mg), chromium (Cr), gold (Au), platinum (Pt), nickel
(Ni), copper (Cu), tungsten (W), aluminum (Al), aluminum-lithium
(Al--Li), magnesium-indium (Mg--In), and magnesium-silver
(Mg--Ag).
As an example, the first pixel electrode 121 may be formed as a
single-layered film, but is not limited thereto. That is, the first
pixel electrode 121 may be formed as a multi-layered film in which
two or more materials are stacked.
When the first pixel electrode 121 is formed as a multi-layered
film, the first pixel electrode 121 may include, as an example, a
reflective film and a transparent or semitransparent electrode
disposed above the reflective film. As another example, the first
pixel electrode 121 may include a reflective film and a transparent
or semitransparent electrode disposed below the reflective film.
For example, the first pixel electrode 121 may have a three-layered
structure of ITO/Ag/ITO, but is not limited thereto.
Here, the transparent or semitransparent electrode may include one
or more selected from the group consisting of indium tin oxide
(ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide
(In.sub.2O.sub.3), indium gallium oxide (IGO), and aluminum zinc
oxide (AZO).
The pixel defining film 130 may be disposed on the first pixel
electrode 121. The pixel defining film 130 includes the opening
OP1a that at least partially exposes the first pixel electrode 121.
The pixel defining film 130 may include an organic material or an
inorganic material. As an example, the pixel defining film 130 may
include materials such as a photoresist, a polyimide resin, an
acrylic resin, a silicon compound, and a polyacrylic resin.
The first organic light emitting layer 141 may be disposed on the
first pixel electrode 121. More specifically, the first organic
light emitting layer 141 may be disposed on a region of the first
pixel electrode 121 to cover the opening OP1a of the pixel defining
film 130. As an example, the first organic light emitting layer 141
may at least partially cover a side wall of the pixel defining film
130.
As an example, the first organic light emitting layer 141 may emit
red light. That is, the first organic light emitting layer 141 may
include a red light emitting material. As another example, the
first organic light emitting layer 141 may emit white light. That
is, the first organic light emitting layer 141 may include a white
light emitting material. Unlike this, the first organic light
emitting layer 141 may have a form in which a red light emitting
layer, a green light emitting layer, and a blue light emitting
layer are stacked to emit white light. In this disclosure, an
example in which the first organic light emitting layer 141 emits
red light and the other organic light emitting layers emit any one
of red light, green light, and blue light will be described
below.
Although not shown, the first organic light emitting layer 141 may
have a multi-layered structure including a hole injection layer
HIL, a hole transport layer HTL, an electron transport layer ETL,
an electron injection layer EIL, and so on.
The common electrode 150 may be disposed on the first organic light
emitting layer 141 and the pixel defining film 130. As an example,
the common electrode 150 may be formed over the first organic light
emitting layer 141 and the pixel defining film 130. As an example,
the common electrode 150 may be a cathode electrode. The common
electrode 150 may include one or more selected from the group
consisting of Li, Ca, LiF/Ca, LiF/Al, Al, Ag, and Mg. Also, the
common electrode 150 may be formed of a low work function material.
As an example, the common electrode 150 may be a transparent or
semitransparent electrode including any one or more selected from
the group consisting of indium tin oxide (ITO), indium zinc oxide
(IZO), zinc oxide (ZnO), indium oxide (In.sub.2O.sub.3), iridium
gallium oxide (IGO), and aluminum zinc oxide (AZO).
The encapsulation layer 160 may be disposed on the first substrate
110 to cover the first organic light emitting layer 141. That is, a
plurality of organic light emitting devices including the first
organic light emitting layer 141 may be disposed between the first
substrate 110 and the encapsulation layer 160. The encapsulation
layer 160 may block penetration of external oxygen and moisture
into the plurality of organic light emitting devices which include
the first organic light emitting layer 141.
As an example, the encapsulation layer 160 may have a form in which
at least one of an organic layer and an inorganic layer is stacked
in a single-layered structure or a multi-layered structure. The
organic layer may include any one selected from the group
consisting of epoxy, acrylate, and urethane acrylate. The inorganic
layer may include any one or more selected from the group
consisting of silicon oxide (SiOx), silicon nitride (SiNx), and
silicon oxynitride (SiONx). As an example, the encapsulation layer
160 may have a form in which a first inorganic layer, an organic
layer disposed on the first inorganic layer, and a second inorganic
layer disposed on the organic layer are stacked.
As another example, the encapsulation layer 160 may be a
transparent insulating substrate. When the encapsulation layer 160
is a transparent insulating substrate, the transparent insulating
substrate may be a glass substrate, a quartz substrate, a
transparent resin substrate, etc. Also, an adhesion layer may be
disposed between the transparent insulating substrate and the first
substrate 110 in order to bond the transparent insulating substrate
and the first substrate 110.
Meanwhile, the encapsulation layer 160 may be omitted when the
color filter and the black matrix BM additionally serve as an
encapsulation layer.
Although not shown, a capping layer may be additionally included
between the common electrode 150 and the encapsulation layer 160.
The capping layer can prevent light incident on the common
electrode 150 from being lost by total reflection. As an example,
the capping layer may be formed as an organic film or an inorganic
film.
The black matrix BM may be disposed on the encapsulation layer 160.
The black matrix BM may be disposed on the encapsulation layer 160
to cover an entire surface of the encapsulation layer 160 except
regions of opening OP2a. A material with high absorption for
visible light may be used for the black matrix BM. As an example,
the black matrix BM may include a metal such as chromium (Cr), a
metal nitride, a metal oxide, a resin material colored in black, or
the like.
The opening OP2a of the black matrix BM may overlap with the first
organic light emitting layer 141 and the opening OP1a of the pixel
defining film 130. Thus, light emitted from the first organic light
emitting layer 141 may pass through the opening OP1a of the pixel
defining film 130 and the opening OP2a of the black matrix BM.
Although not shown, a buffer layer or an organic layer may be
formed between the black matrix BM and the encapsulation layer 160.
The buffer layer or the organic layer may be formed in a
single-layered structure or a multi-layered structure. The opening
OP2a of the black matrix BM may completely expose the opening OP1a
of the pixel defining film 130 in a plan view.
The first color filter CF1, the second color filter CF2, and the
third color filter CF3 may be disposed on the black matrix BM. The
black matrix BM may be disposed at a boundary between the plurality
of color filters including the first color filter CF1, the second
color filter CF2, and the third color filter CF3.
The first color filter CF1 may selectively transmit red light.
Here, the red light may have a wavelength ranging from about 620 nm
to about 750 nm. The second color filter CF2 may selectively
transmit green light. Here, the green light may have a wavelength
ranging from about 495 nm to about 570 nm. The third color filter
CF3 may selectively transmit blue light. Here, the blue light may
have a wavelength ranging from about 450 nm to about 495 nm. As an
example, the first color filter CF1, the second color filter CF2,
and the third color filter CF3 may include a resin containing
pigment or dye. As another example, the first color filter CF1, the
second color filter CF2, and the third color filter CF3 may include
different materials which are formed through different
processes.
As an example, the first color filter CF1, the second color filter
CF2, and the third color filter CF3 may have a rhombus shape. Thus,
it is possible to minimize separation distances between the first
color filter CF1 and its adjacent color filters. Meanwhile, in FIG.
1, the adjacent color filters are shown as not overlapping with
each other, but the adjacent color filters may overlap with each
other. When the adjacent color filters overlap with each other, an
overlapped portion may overlap with the black matrix BM. Also, the
shape and size of the first color filter CF1, the second color
filter CF2, and the third color filter CF3 are not limited to those
shown in FIGS. 1 and 2. Meanwhile, in this disclosure, an example
in which a color filter is disposed on the black matrix BM has been
described. Unlike this, the black matrix BM may be disposed on the
color filter.
FIG. 3 is a view for comparison between FIG. 1, which is a plan
view of a first pixel, and FIG. 2, which is a sectional view taken
along line I-I'. FIG. 4 is a plan view showing a color filter and
an opening of a black matrix of an organic light emitting display
device according to a comparative example. For convenience of
description, some elements included in the organic light emitting
display device may be omitted in FIGS. 3 and 4.
Referring to FIG. 3, the opening OP2a of the black matrix BM may
have a circular shape. That is, the opening OP2a of the black
matrix BM has a circular shape and thus can omnidirectionally and
uniformly induce diffraction of light L1 on the basis of the
virtual center point cp. Thus, even when light introduced from an
external source (hereinafter referred to as "external light") is
reflected by the first pixel electrode 121, the organic light
emitting display device according to an embodiment of the present
inventive concept may omnidirectionally and uniformly induce
diffraction of the reflected light L1. Accordingly, with the
organic light emitting display device according to an embodiment of
the present inventive concept, it is possible to alleviate color
separation due to external light and visibility degradation due to
external light reflection.
Referring to FIG. 4, an organic light emitting display device
according to a comparative example includes a black matrix BMa
having a rhombic opening BM_OP and a quadrangular color filter CFa.
That is, the opening BM_OP of the black matrix BMa does not have
uniform diffraction of light L2 on the basis of a virtual center
point cpa. More specifically, the organic light emitting display
device according to the comparative example has different
diffraction of light L2 at a vertex a1 and a side a2 of the rhombic
opening BM_OP of the black matrix. Thus, even when the external
light is reflected, the organic light emitting display device
according to the comparative example does not have uniform
diffraction of light L2 (i.e., light L2 is biased in a certain
direction), and thus color separation may be generated.
FIG. 5 is a view showing that color separation is alleviated in an
organic light emitting display device according to an embodiment of
the present inventive concept. FIG. 6 is a view showing color
separation of the organic light emitting display device according
to the comparative example shown in FIG. 4.
It can be seen from FIG. 6 that color separation is generated in
the form of a letter X in the organic light emitting display device
according to the comparative example. On the other hand, it can be
seen from FIG. 5 that color separation due to external light is
alleviated by the organic light emitting display device according
to an embodiment of the present inventive concept by
omnidirectionally and uniformly inducing diffraction of light.
Meanwhile, the organic light emitting display device according to
an embodiment of the present inventive concept does not include a
polarizing plate. That is, the organic light emitting display
device according to an embodiment of the present inventive concept
can reduce reflection of external light without using the
polarizing plate by using the color filter and the black matrix BM
as disclosed in the embodiment. Also, it is possible to alleviate
color separation by forming the opening BM_OP of the black matrix
BMa in a circular shape.
FIG. 7 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept. FIG. 8 is a sectional view taken along
line II-II' shown in FIG. 7. For convenience of description,
contents which are described in the foregoing embodiments with
reference to FIGS. 1 to 6 will be omitted in the following
description. The same reference numerals will be used for the same
elements as those shown in FIGS. 1 to 6.
Referring to FIGS. 7 and 8, an opening OP2b of a black matrix BM1
has a smaller area than the opening OP1a of the pixel defining film
130. That is, the opening OP2b of the black matrix BM1 may fully
overlap with a region of the first pixel electrode 121 exposed by
the opening OP1a of the pixel defining film 130.
Accordingly, since the opening OP2b of the black matrix BM1 has a
smaller area than the region of the first pixel electrode 121
exposed by the opening OP1a of the pixel defining film 130,
external light L3a may have the same form as light L3b reflected by
the first pixel electrode 121. Thus, the organic light emitting
display device according to another embodiment of the present
inventive concept may alleviate reflected color separation due to
external light.
Also, the opening OP2b of the black matrix BM1 may have a circular
shape. Thus, even when the external light L3a is reflected by the
first pixel electrode 121, the organic light emitting display
device may omnidirectionally and uniformly induce diffraction of
the reflected light L3b. Thus, the organic light emitting display
device according to another embodiment of the present inventive
concept may alleviate color separation due to external light.
Meanwhile, as long as the opening OP2b of the black matrix BM1 has
a smaller area than the opening OP1a of the pixel defining film
130, the shape of the opening OP2b of the black matrix BM1 is not
limited to a circular shape. This will be described below in detail
with reference to FIGS. 9A and 9B. For convenience of description
in FIGS. 9A and 9B, the reference numerals of all the black
matrices will be marked as "BM1."
FIGS. 9A and 9B is a view showing examples of the shape of the
opening of the black matrix shown in FIG. 7. Referring to FIG. 9A,
an opening OP2c of the black matrix BM1 may have a polygonal shape
close to a circular shape. Alternatively, referring to FIG. 9B, an
opening OP2d of the black matrix BM1 may have a quadrangular
shape.
The shape of the opening of the black matrix BM1 is not limited to
those shown in FIGS. 8 and 9, and the opening of the black matrix.
BM1 may be formed in various shapes (such as an ellipse, a rhombus,
and a parallelogram) in consideration of a required aperture ratio,
required reflectivity, process conditions, and so on.
Also, a plurality of openings of the black matrix BM1 may have
different shapes and areas. For example, the plurality of openings
of the black matrix BM1 may have different shapes and areas
depending on the type of an overlapping color filter. As an
example, the diffraction degrees of wavelengths included in the
external light (red>green>blue) and the brightness and
lifespan of the organic light emitting layer are different. Thus,
the shapes and areas of the plurality of openings of the black
matrix BM1 may be determined in consideration of the difference. As
an example, an opening overlapping with a green color filter among
the plurality of openings of the black matrix BM1 may have
relatively the smallest area.
FIG. 10 is a view showing an interval between openings of a pixel
defining film adjacent to an organic light emitting display device
according to another embodiment of the present inventive concept.
The following description with reference to FIG. 10 is based on a
reference pixel PX_ref overlapping with a reference color filter
CF_ref.
Referring to FIG. 10, an opening OP2_ref of a black matrix BM_ref
has a smaller area than an opening OP1_ref of a pixel defining
film. That is, the opening OP2_ref of the black matrix BM_ref may
fully overlap with a region of a pixel electrode PE exposed by the
opening OP1_ref of the pixel defining film.
Thus, since the opening OP2_ref of the black matrix BM_ref has a
smaller area than the pixel electrode PE capable of reflecting
external light, the external light and light reflected by the pixel
electrode PE may have the same form. Also, the opening OP2b_ref of
the black matrix BM_ref may have a circular shape. Accordingly, the
organic light emitting display device according to another
embodiment of the present inventive concept may alleviate reflected
color separation due to external light.
Referring to FIG. 10, shortest distances d between the opening
OP1_ref of the pixel defining film for exposing the pixel electrode
PE and openings of adjacent pixel defining films may be the same as
each other. Here, openings adjacent in a first direction d1 and a
third direction d3 with reference to FIG. 10 are excluded from the
openings of the adjacent pixel defining films.
When the shortest distances d between the opening OP1_ref of the
pixel defining film for exposing the pixel electrode PE and
openings of adjacent pixel defining films are different from each
other, color crosstalk may occur between two adjacent pixels having
a relatively small shortest distance d. As a result, colors in the
two adjacent pixels may be mixed with each other.
With the organic light emitting display device shown in FIG. 10,
the shortest distances d between the opening OP1_ref of the pixel
defining film for exposing the pixel electrode PE and openings of
adjacent pixel defining films may be the same, and thus it is
possible to alleviate color crosstalk between adjacent pixels. As
another example, in addition to the case where the opening OP2_ref
of the black matrix BM_ref has a smaller area than the opening
OP1_ref of the pixel defining film (i.e., even when the area of the
opening OP2_ref of the black matrix BM_ref is larger than or equal
to the area of the opening OP1_ref of the pixel defining film), the
shortest distances d between the opening OP1_ref of the pixel
defining film and openings of adjacent pixel defining films may be
the same.
FIG. 11 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept. FIG. 12 is a sectional view taken along
line III-III' shown in FIG. 11. However, duplicate content of the
foregoing description with reference to FIGS. 1 to 10 will be
omitted in the following description.
Referring to FIGS. 11 and 12, an opening OP1b of a pixel defining
film 130a may have a circular shape. Also, an opening OP2a of a
black matrix BM may have a substantially circular shape. That is,
the opening OP1b of the pixel defining film 130a and the opening
OP2a of the black matrix BM have circular shapes, and thus it is
possible to omnidirectionally disperse light L1 reflected by a
first pixel electrode 121. That is, the organic light emitting
display device according to another embodiment of the present
inventive concept may omnidirectionally and uniformly induce
diffraction of the light L1 reflected by the first pixel electrode
121, and thus it is possible to alleviate color separation due to
external light and visibility degradation due to reflection of
external light.
Meanwhile, in FIGS. 11 and 12, the opening OP1b of the pixel
defining film 130a and the opening OP2a of the black matrix BM are
shown as having the same area, but are not limited thereto. As an
example, the opening OP2a of the black matrix BM may have a smaller
area than the opening OP1b of the pixel defining film 130a. Thus,
the external light and the light reflected by the first pixel
electrode 121 may have the same form.
FIG. 13 is a plan view showing an opening of a black matrix and a
color filter of an organic light emitting display device according
to another embodiment of the present inventive concept. For
convenience of description, the remaining elements other than a
color filter and an opening of a black matrix will be omitted in
FIG. 13.
Referring to FIG. 13, a first color filter CFa1 and a third color
filter CFa3 may have a quadrangular shape. A second color filter
CFa2 may be formed overall along the same column, other than an
opening OP2e of a black matrix BM2.
Here, as an example, the first color filter CFa1 may be a red color
filter, and the second color filter CFa2 may be a green color
filter. Also, as an example, the third color filter CFa3 may be a
blue color filter. Locations of the first color filter CFa1 and the
third color filter CFa3 may be exchangeable with each other.
That is, the organic light emitting display device according to
another embodiment of the present inventive concept shown in FIG.
13 is different from the organic light emitting display device
according to an embodiment shown in FIG. 1 in terms of the shapes
of the color filters. However, even in this case, the opening OP2e
of the black matrix BM2 may have a circular shape.
Thus, even when external light is reflected by a plurality of pixel
electrodes, it is possible to omnidirectionally and uniformly
induce diffraction of the reflected light. Accordingly, with the
organic light emitting display device according to another
embodiment of the present inventive concept, it is possible to
alleviate color separation due to external light and visibility
degradation due to external light reflection.
FIG. 14 is a plan view showing an opening of a black matrix and a
color filter of an organic light emitting display device according
to still another embodiment of the present inventive concept. FIG.
15 is a plan view showing a color filter and an opening of a black
matrix of an organic light emitting display device according to a
comparative example. For convenience of description, only a black
matrix, an opening of the black matrix, and a color filter have
been shown in FIGS. 14 and 15.
Referring to FIG. 14, a color filter CF1b may sufficiently overlap
with a black matrix BM3. Thus, light L4 reflected through a pixel
electrode or the like may minimize diffraction in a side portion
(an edge region) of the color filter CFR). As an example, an
overlap distance t1 between the color filter CF1b and the black
matrix BM3 may range from about 6 .mu.m to about 12 .mu.m.
On the other hand, referring to FIG. 15, an organic light emitting
display device according to a comparative example includes a black
matrix BMa having a rhombic opening BM_OP and a quadrangular color
filter CFa. That is, the organic light emitting display device
according to the comparative example has a short overlap distance
t2 between the color filter CFa and the black matrix BMa. Thus,
diffraction of reflected light L5 may occur in a side portion of
the color filter CFa. When the diffraction of the reflected light
L5 occurs, color separation and visibility degradation may
occur.
Meanwhile, as long as the color filter CF1b sufficiently overlaps
with the black matrix BM3, an opening OP2f of the black matrix BM3
need not have the same shape as the color filter CF1b.
Even when the opening of the black matrix BM3 has a circular shape,
the overlap distance t1 between the color filter CF1b and the black
matrix BM3 may range, for example, from about 6 .mu.m to about 12
.mu.m.
FIG. 16 is a plan view showing a pixel layout of an organic light
emitting display device according to another embodiment of the
present inventive concept. FIG. 17 is a sectional view taken along
line IV1-IV1', line IV2-IV2', and line IV3-IV3' shown in FIG. 16.
In FIGS. 16 and 17, a first pixel PX1a, a second pixel PX2a, and a
third pixel PX3a will be described as an example. However,
duplicate content of the foregoing description with reference to
FIGS. 1 to 15 will be omitted in the following description. Also,
an opening of a first color filter layer CFL1 will not be shown in
FIG. 16 in order to avoid confusion with other elements.
Referring to FIGS. 16 and 17, the first color filter layer CFL1 may
be disposed on a black matrix BM. The first color filter layer CFL1
may include a plurality of openings having a first opening OP3a1
and a second opening OP3a2. Also, the first color filter layer CFL1
overlaps with a third organic light emitting layer 143, an opening
OP1a3 of a pixel defining film 130, and an opening OP2a3 of the
black matrix BM. That is, the first color filter layer CFL1 may be
disposed on the black matrix BM to cover an entire surface of the
black matrix BM except regions of the plurality of openings.
More specifically, the first color filter layer CFL1 may be formed
to surround openings OP2a1 and OP2a2 of the black matrix BM when
viewed from the top.
As an example, the first color filter layer CFL1 may be a blue
color filter layer selectively transmitting blue light. Thus, the
third pixel PX3a may display a blue color.
A first color filter CF1a may be disposed on the first color filter
layer CFL1. The first color filter CF1a may overlap with a first
organic light emitting layer 141, an opening OP1a1 of the pixel
defining film 130, and the opening OP2a1 of the black matrix BM. As
an example, the first color filter CF1a may be a red color filter
selectively transmitting red light. Thus, the first pixel PX1a may
display a red color.
A second color filter CF2a may be disposed on the first color
filter layer CFL1. The second color filter CF2a may overlap with a
second organic light emitting layer 142, an opening OP1a2 of the
pixel defining film 130, and the opening OP2a2 of the black matrix
BM. As an example, the second color filter CF2a may be a green
color filter selectively transmitting green light. Thus, the second
pixel PX2a may display a green color.
The first color filter CF1a and the second color filter CF2a are
not formed overall on the black matrix BM, unlike the first cc for
filter layer CFL1.
FIG. 18 is a diagram illustrating an improvement of reflective
dispersion of the organic light emitting display device shown in
FIG. 16.
Referring to FIGS. 16 to 18, after the first color filter layer
CFL1 is formed, the first color filter CF1a and the second color
filter CF2a are formed on the first color filter layer CFL1. The
first color filter layer CFL1 is formed overall on the black matrix
BM, and the first color filter CF1a and the second color filter
CF2a are formed in an island shape to at least partially overlap
with the first color filter layer CFL1. Thus, the black matrix BM
may not include an exposed region. Thus, even when at least one of
the first color filter CF1a and the second color filter CF2a is
misaligned with respect to a center line SL1 or SL2 during a
process an exposed area of the black matrix BM may be maintained at
a constant value because the first color filter layer CFL1 is
formed to cover an entire surface of the black matrix BM except
regions of the plurality of openings. Here, the degree to which the
first color filter CF1a and the first color filter layer CFL1
overlap with each other and the degree to which the second color
filter CF2a and the first color filter layer CFL1 overlap with each
other may be determined in consideration of color crosstalk and
design margins.
That is, since the first color filter layer CFL1 is formed to cover
an entire surface of the black matrix BM except regions of the
plurality of openings, a region in which the first color filter
layer CFL1 and the black matrix BM are exposed may be maintained in
a displayed region DA3 although at least one of the first color
filter CF1a and the second color filter CF2a is misaligned with
respect to the center line SL1 or SL2.
When an area in which the black matrix BM is exposed is different
for each location during the process, a dispersion imbalance may
occur for each location. This also means that reflectivity of
external light may change for each location.
With the organic light emitting display device according to another
embodiment of the present inventive concept, it is possible to
alleviate a dispersion imbalance and a reflectivity difference for
each region by maintaining the region in which the first color
filter layer CFL1 and the black matrix BM are exposed in the
displayed region DA3.
The openings OP2a1, OP2a2, and OP2a3 of the black matrix BM may
have a circular shape. That is, since the openings OP2a1, OP2a2,
and OP2a3 of the black matrix BM have a circular shape, the organic
light emitting display device may omnidirectionally and uniformly
induce light diffraction. Thus, even when external light is
reflected by first to third pixel electrodes 121 to 123, the
organic light emitting display device may omnidirectionally and
uniformly induce light diffraction. Accordingly, with the organic
light emitting display device according to another embodiment of
the present inventive concept, it is possible to alleviate color
separation due to external light and visibility degradation due to
external light reflection.
FIGS. 19 to 26 are diagrams illustrating a process of manufacturing
the organic light emitting display device shown in FIG. 16.
However, duplicate content of the foregoing description with
reference to FIGS. 16 to 18 will be omitted in the following
description.
Referring to FIGS. 19 to 22, a black matrix BM may be formed oil an
encapsulation layer 160. The black matrix BM may be disposed on the
encapsulation layer 160 except regions of a plurality of openings
including openings OP2a1, OP2a2, and OP2a3. A material with high
absorption for visible light may be used for the black matrix BM.
Although not shown, a buffer layer or an organic layer may be
formed between the black matrix BM and the encapsulation layer 160.
The buffer layer or the organic layer may be formed in a
single-layered structure or a multi-layered structure.
Referring to FIGS. 23 and 24, a first color filter layer CFL1 may
be disposed on the black matrix BM. The first color filter layer
CFL1 may be formed overall on the black matrix BM except regions of
a plurality of openings having a first opening OP3a1 and a second
opening OP3a2.
Referring to FIGS. 25 and 26, a first color filter CF1a and a
second color filter CF2a may be sequentially formed on the first
color filter layer CFL1. The first color filter CF1a may be formed
to cover the first opening OP3a1 of the first color filter layer
CFL1. The second color filter CF2a may be formed to cover the
second opening OP3a2 of the first color filter layer CFL1. The
order in which the first color filter CF1a and the second color
filter CF2a are formed is not particularly limited.
A method of forming the first color filter layer CFL1, the first
color filter CF1a, and the second color filter CF2a is not
particularly limited. For example, the first color filter layer
CFL1, the first color filter CF1a, and the second color filter CF2a
may be formed through a photo lithography process or an inkjet
process. Also, the first color filter layer CFL1, the first color
filter CF1a, and the second color filter CF2a need not be formed
through the same process. For example, the first color filter layer
CFL1 may include a polymer material as the first color filter layer
CFL1 is formed through the photo process. Thus, the first color
filter CF1a and the second color filter CF2a may include an ink
material as the first color filter CF1a and the second color filter
CF2a are formed through the inkjet process.
An organic light emitting display device having a low-reflection
and no-change structure according to another embodiment will be
described below with reference to FIGS. 27 to 30. For comparison
with FIG. 17, the following description will be provided with
reference to the sectional views of FIGS. 27 to 30. However,
duplicate content of the foregoing description with reference to
FIGS. 16 to 26 will be omitted in the following description.
FIG. 27 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept.
Referring to FIG. 27, a second color filter layer CFL2 may be
disposed on a first color filter layer CFL1. The second color
filter layer CFL2 may include a plurality of openings having a
first opening OP4a1 and a second opening OP4a2. Also, the second
color filter layer CFL2 overlaps with a first organic light
emitting layer 141, an opening OP1a1 of a pixel defining film 130,
and an opening OP2a1 of a black matrix BM. That is, the second
color filter layer CFL2 may be formed to cover an entire surface of
the first color filter layer CFL1 except regions of the plurality
of openings having a first opening OP4a1 and a second opening
OP4a2.
More specifically, the second color filter layer CFL2 may be formed
to surround openings OP2a2 and OP2a3 of the black matrix BM when
viewed from the top. In other words, the second color filter layer
CFL2 may be formed to surround openings OP3a1 and OP3a2 of the
first color filter layer CFL1 when viewed from the top.
That is, the second color filter layer CFL2 is formed to cover an
entire surface of the first color filter layer CFL1 except regions
of the second opening OP4a2. At this point, the second color filter
layer CFL2 covers the opening OP2a1 of the black matrix BM. As an
example, the second color filter layer CFL2 may be a red color
filter layer selectively transmitting red light. Thus, a first
pixel PX1a may display a red color.
A second color filter CF2a may be disposed on the second color
filter layer CFL2. The second color filter CF2a may overlap with a
second organic light emitting layer 142, an opening OP1a2 of the
pixel defining film 130, and the opening OP2a2 of the black matrix
BM. As an example, the second color filter CF2a may be a green
color filter selectively transmitting green light. Thus, a second
pixel PX2a may display a green color.
That is, the organic light emitting display device shown in FIG. 27
may include the second color filter layer CFL2 instead of the first
color filter CF1a.
FIG. 28 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept.
Referring to FIG. 28, a third color filter layer CFL3 may be
disposed on the second color filter layer CFL2. The third color
filter layer CFL3 may include a plurality of openings having a
first opening OP5a1 and a second opening OP5a2. Also, the third
color filter layer CFL3 overlaps with the second organic light
emitting layer 142, the opening OP1a2 of the pixel defining film
130, and the opening OP2a2 of the black matrix BM. That is, the
third color filter layer CFL3 may be formed to cover an entire
surface of the second color filter layer CFL2 except regions of a
plurality of first openings OP5a1 and a plurality of second
openings OP5a2.
More specifically, the third color filter layer CFL3 may be formed
to surround the openings OP2a1 and OP2a3 of the black matrix BM
when viewed from the top.
As an example, the third color filter layer CFL3 may be a green
color filter layer selectively transmitting green light. Thus, the
second pixel PX2a may display a green color.
That is, the organic light emitting display device shown in FIG. 28
may include the third color filter layer CFL3 instead of the second
color filter CF2a.
FIG. 29 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept.
Referring to FIG. 29, a fourth color filter CF4 may be disposed on
the first color filter layer CFL1. The fourth color filter CF4 may
overlap with the first organic light emitting layer 141, the second
organic light emitting layer 142, the openings OP1a1 and OP1a2 of
the pixel defining film 130, and the openings OP2a1 and OP2a2 of
the black matrix BM. As an example, the fourth color filter CF4 may
be a yellow color filter selectively transmitting yellow light.
The types of the colors of the first color filter layer CFL1, the
second color filter layer CFL2, and the third color filter layer
CFL3 and the order in which the first color filter layer CFL1, the
second color filter layer CFL2, and the third color filter layer
CFL3 are formed are not particularly limited. However, when the
first color filter layer CFL1 formed on the lowest portion among
the color filters or the color filter layers is a blue color filter
layer having relatively low transmissivity, it is possible to
enhance quality of displayed images. Also, the first color filter
layer CFL1, the second color filter layer CFL2, and the third color
filter layer CFL3 have been described as a blue color filter layer,
a red color filter layer, and a green color filter layer,
respectively, but are not limited thereto. For example, each of the
first color filter layer CFL1, the second color filter layer CFL2,
and the third color filter layer CFL3 may be any one of a cyan
color filter layer, a magenta color filter layer, and a yellow
color filter layer.
FIG. 30 is a sectional view showing an organic light emitting
display device according to another embodiment of the present
inventive concept.
Referring to FIG. 30, unlike FIG. 17, a first color filter CF1c and
a second color filter CF2c may be formed before a first color
filter layer CFL1a is formed. That is, the first color filter CF1c
and the second color filter CF2c may be sequentially formed on a
black matrix BM, and the first color filter layer CFL1a may be
formed to cover an entire surface of the remaining regions other
than regions where the first color filter CF1a and the second color
filter CF2a are disposed. That is, the first color filter layer
CFL1a may be formed to surround openings OP2a1 and OP2a2 of the
black matrix BM when viewed from the top.
FIG. 31 is a plan view showing a pixel layout of an organic light
emitting display device according to still another embodiment of
the present inventive concept. FIG. 32 is a sectional view taken
along line V1-V1', line V2-V2', and line V3-V3' shown in FIG.
31.
Referring to FIGS. 31 and 32, openings OP2b1, OP2b2, and OP2b3 of a
black matrix BM1a have smaller areas than openings OP1a1, OP1a2,
and OP1a3 of a pixel defining film 130. That is, the openings
OP2b1, OP2b2, and OP2b3 of the black matrix BM1a may fully overlap
with regions of a first pixel electrode 121 exposed by the openings
OP1a1, OP1a2, and OP1a3 of the pixel defining film 130.
Accordingly, since the openings OP2b1, OP2b2, and OP2b3 of the
black matrix BM1a have smaller areas than regions of the first
pixel electrode 121, a second pixel electrode 122, and a third
pixel electrode 123 exposed by the openings OP1a1, OP1a2, and OP1a3
of the pixel defining film 130, external light may have the same
form as light reflected by the first pixel electrode 121, the
second pixel electrode 122, and the third pixel electrode 123.
Also, the openings OP2b1, OP2b2, and OP2b3 of the black matrix BM1a
may have a circular shape. Thus, even when external light is
reflected by at least one of the first pixel electrode 121, the
second pixel electrode 122, and the third pixel electrode 123, it
is possible to omnidirectionally and uniformly induce diffraction
of reflected light. Accordingly, with the organic light emitting
display device according to still another embodiment of the present
inventive concept, it is possible to alleviate color separation due
to external light and visibility degradation due to external light
reflection.
As long as the openings OP2b1, OP2b2, and OP2b3 of the black matrix
BM1a have smaller areas than the openings OP1a1, OP1a2, and OP1a3
of the pixel defining film 130, the openings OP2b1, OP2b2, and
OP2b3 of the black matrix BM1a are not limited to a circular
shape.
Meanwhile, in FIGS. 16 to 32, the opening of the first color filter
layer CFL1 is shown as having the same size as the first color
filter CF1a or the second color filter CF2a. However, this is for
convenience of description, and the present inventive concept is
not limited thereto.
According to embodiments of the present inventive concept, it is
possible to alleviate reflected color separation due to external
light.
It is also possible to reduce costs by using no polarizing
plate.
It is also possible to implement uniform dispersion characteristics
and reduce reflectivity.
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